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46-583: Cinder Cone is a cinder cone volcano in Lassen Volcanic National Park within the United States . It is located about 10 mi (16 km) northeast of Lassen Peak and provides an excellent view of Brokeoff Mountain , Lassen Peak , and Chaos Crags . The cone was built to a height of 750 ft (230 m) above the surrounding area and spread ash over 30 sq mi (78 km). Then, like many cinder cones, it

92-479: A crater with a double rim ( photo ), probably created by two different phases of one eruptive period. The cone also has a widespread ash deposit identifiable for 8 to 10 mi (13 to 16 km) from the cone. Blocks of red, cemented scoria within the Painted Dunes lava flows ( photo ) are pieces of this earlier cone, which were carried away by the flowing lava. When Cinder Cone formed, the magma feeding

138-436: A cinder cone eruption, the magma has lost most of its gas content. This gas-depleted magma does not fountain but oozes quietly into the crater or beneath the base of the cone as lava. Lava rarely issues from the top (except as a fountain) because the loose, uncemented cinders are too weak to support the pressure exerted by molten rock as it rises toward the surface through the central vent. Because it contains so few gas bubbles,

184-409: A cinder cone is usually basaltic to andesitic in composition. It is often glassy and contains numerous gas bubbles "frozen" into place as magma exploded into the air and then cooled quickly. Lava fragments larger than 64 mm across, known as volcanic bombs , are also a common product of cinder cone eruptions. The growth of a cinder cone may be divided into four stages. In the first stage,

230-465: A few visible crystals of the minerals olivine , plagioclase , and quartz . The early group of volcanic deposits at Cinder Cone, which have relatively little titanium, include older scoria cone, the Old Bench flow, the two Painted Dunes flows, and the lower part of the widespread ash layer. The second group, erupted later and comparatively rich in titanium, consists of the large, younger scoria cone,

276-409: A low-rimmed scoria ring forms around the erupting event. During the second stage, the rim is built up and a talus slope begins to form outside the rim. The third stage is characterized by slumping and blasts that destroy the original rim, while the fourth stage is characterized by the buildup of talus beyond the zone where cinder falls to the surface (the ballistic zone ). During the waning stage of

322-581: A new vent. Eruptions continued for nine years, built the cone to a height of 424 meters (1,391 ft), and produced lava flows that covered 25 km (9.7 sq mi). The Earth's most historically active cinder cone is Cerro Negro in Nicaragua. It is part of a group of four young cinder cones NW of Las Pilas volcano. Since its initial eruption in 1850, it has erupted more than 20 times, most recently in 1995 and 1999. Satellite images suggest that cinder cones occur on other terrestrial bodies in

368-807: A result, the USGS began reevaluating the risks posed by other potentially active volcanoes in the Cascade Range, including those in Lassen Volcanic National Park. Since that time, USGS scientists have been working in cooperation with the National Park Service to better understand volcanic hazards in the Lassen area. As part of this work, the history of Cinder Cone has been reexamined. Most of the features of Cinder Cone have changed little since Harkness first described them in

414-464: A silica content between 52% and 57%. Although classification by mineral content is preferred by the IUGS , this is impractical for glassy or very fine-grained volcanic rock, and then the chemical TAS classification is used. Basaltic andesite is then defined as volcanic rock with a silica content of 52% to 57% and a total alkali content ( K 2 O plus Na 2 O ) of less than about 6%, corresponding to

460-656: A single, typically cylindrical, vent. As the gas-charged lava is blown violently into the air, it breaks into small fragments that solidify and fall as either cinders, clinkers, or scoria around the vent to form a cone that often is symmetrical; with slopes between 30 and 40°; and a nearly circular ground plan. Most cinder cones have a bowl-shaped crater at the summit. Cinder cones range in size from tens to hundreds of meters tall. They are composed of loose pyroclastic material ( cinder or scoria ), which distinguishes them from spatter cones , which are composed of agglomerated volcanic bombs . The pyroclastic material making up

506-418: A terrible height" and that they had walked for 10 mi (16 km) over rocks that burned through their boots. This narrative complemented several accounts of activity at the volcano across 1850 and 1851, which all claimed to observe the eruptions from at least 40 mi (64 km) away. During the early 1870s, medical doctor and amateur scientist H. W. Harkness from San Francisco, California , visited

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552-530: Is not separately defined in the QAPF classification , which is based on the relative percentages of quartz , alkali feldspar , plagioclase feldspar , and feldspathoids , but would fall in the basalt-andesite field. This corresponds to rock in which feldspathoid makes up less than 10% and quartz less than 20% of the total QAPF fraction, and in which at least 65% of the feldspar is plagioclase. Basaltic andesite would be further distinguished from basalt and andesite by

598-442: Is very low and the eruptions are spread out in space and time. This prevents any one eruption from establishing a system of " plumbing " that would provide an easy path to the surface for subsequent eruptions. Thus each eruption must find its independent path to the surface. Basaltic andesite Basaltic andesite is a fine-grained ( aphanitic ) igneous rock that is moderately low in silica and low in alkali metal oxides . It

644-691: The Earth's crust is undergoing extension. For example, mid- Cenozoic volcanic sequences in western Mexico , southwestern New Mexico , and southeastern Arizona are capped by basaltic andesite of the Southern Cordilleran Basaltic Andesite (SCORBA) suite, which may be the most extensive Cenozoic mafic suite in North America. Mount Mazama , a large composite volcano in south-central Oregon, consists of several overlapping basaltic andesite shields. Basaltic andesite

690-408: The 1850s as the age of Cinder Cone, it does not provide an actual age for its eruption. By measuring levels of carbon-14 in samples of wood from trees killed by the eruption of Cinder Cone, USGS scientists obtained a radiocarbon date for the eruption of between 1630 and 1670. Such a date is also consistent with the remnant magnetization preserved in the lava flows. The series of eruptions that produced

736-468: The 1850s is well known and is different from the remnant magnetizations at Cinder Cone, the lava flows there could not have been erupted in 1850 or 1852. Also, there are no discernible differences in the magnetic orientation recorded by any of the Cinder Cone lava flows, and so the flows had to be extruded during an interval of less than 50 years. Although paleomagnetic evidence can be used to rule out

782-625: The 1850s, the details remain inconsistent. The first such report, which was published in the August 21, 1850, edition of the Daily Pacific News (a San Francisco newspaper), cited an unnamed observer who claimed to have seen "burning lava still running down the sides" at Cinder Cone. In 1859, the San Francisco Times published an article with testimony from Wozencraft and a companion in which they claimed to have seen flames in

828-451: The 1870s, but all of the assumptions on which Finch based his conclusions have now been shown to be incorrect. Through new field and laboratory work and by reinterpreting data from previous studies, USGS scientists have shown that the entire eruptive sequence at Cinder Cone represents a single continuous event. Because the orientation of the Earth's magnetic field in northern California during

874-503: The 1870s, when many people thought it was only a few decades old. Later, the cone and associated lava flows were thought to have formed about 1700 or during a 300-year- long series of eruptions ending in 1851. Recent studies by U.S. Geological Survey (USGS) scientists, working in cooperation with the National Park Service to better understand volcanic hazards in the Lassen area, have firmly established that Cinder Cone

920-811: The Cinder Cone area. Intrigued by the "apparent youthfulness" of the area's volcanic landmarks, he observed several features to argue that Cinder Cone was only about 25 years old. He presented his conclusions at a meeting of the California Academy of Sciences , and was contacted by Academy member Henry Chapman, who informed him of the gold prospector story. A number of other people reached out to Harkness about seeing volcanic activity in Lassen in about 1851, such as O. M. Wozencraft , which led Harkness to think that Cinder Cone had erupted recently. Though there were multiple reports of eruptive activity near Lassen in Northern California newspapers during

966-465: The Coalstoun Lakes volcanic field , and some cinder cones on Mauna Kea are monogenetic cinder cones. However, not all cinder cones are monogenetic, with some ancient cinder cones showing intervals of soil formation between flows that indicate that eruptions were separated by thousands to tens of thousands of years. Monogenetic cones likely form when the rate of magma supply to a volcanic field

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1012-605: The O1 field in the TAS diagram. A basaltic andesite (or andesite) enriched in magnesium and depleted in titanium , with more than 8% MgO and less than 0.5% TiO 2 , is termed a boninite . Basaltic andesite is found in volcanic arcs , such as those of Central America , the Andes of South America , and the Cascades of North America . Basaltic andesite is also common where

1058-471: The Painted Dunes flows dammed the Grassy Creek stream, which is fed by water from the central plateau of the national park area. Water from this lake feeds Butte Lake , located 2 mi (3.2 km) to the north. Butte Lake is the sole remaining fragment of a much larger body of water filled with lava during Cinder Cone's eruptive period. Diatomite sediment, formed from the aggregation of diatoms on

1104-415: The ash deposits. In regard to the explosive eruption, he concluded that "Whatever may be the historical testimony as to the time of the eruption, the geologic evidence clearly demonstrates that it must have occurred long before the beginning of the present century" (before 1800). Diller therefore speculated that the explosive eruption had occurred between about 1675 and 1700 and that the younger, quiet eruption

1150-577: The date of Wozencraft's sighting to be the winter of 1850–1851. The first geologist to study Cinder Cone was Joseph Diller. One of the first USGS scientists to study volcanoes, Diller took careful notes on Cinder Cone and interviewed many Native Americans and European trappers and settlers inhabiting the Lassen region during 1850, none of whom remembered volcanic activity there. Aware of an "emigrant road" (the Nobles Emigrant Trail ), which had been utilized by settlers coming to California in

1196-599: The dispersion of ejected scoria particles. For example, cinder cones on Mars seem to be more than two times wider than terrestrial analogues as lower atmospheric pressure and gravity enable wider dispersion of ejected particles over a larger area. Therefore, it seems that erupted amount of material is not sufficient on Mars for the flank slopes to attain the angle of repose and Martian cinder cones seem to be ruled mainly by ballistic distribution and not by material redistribution on flanks as typical on Earth. Cinder cones often are highly symmetric, but strong prevailing winds at

1242-438: The early 1850s, that passes close to the base of Cinder Cone, he interviewed a number of people who "crossed the trail" in 1853. They noted that a large, solitary willow bush ( Salix scouleriana ) near the summit of Cinder Cone had not been destroyed by any eruptive activity. The bush is still alive and has not been altered much since. Because the willow at the summit of Cinder Cone was already mature in 1853, Diller concluded it

1288-565: The entire eruptive sequence. [REDACTED]  This article incorporates public domain material from websites or documents of the United States Geological Survey . Cinder cone A cinder cone (or scoria cone ) is a steep conical hill of loose pyroclastic fragments, such as volcanic clinkers, volcanic ash, or scoria that has been built around a volcanic vent . The pyroclastic fragments are formed by explosive eruptions or lava fountains from

1334-427: The eruption changed composition, shifting from basaltic andesite to andesite before returning to basaltic andesite with increased titanium content. While basaltic andesites are volcanic rocks containing 53 to 57% silica , andesites are those containing 57 to 63% silica. The lava flows and scorias at the volcano closely resemble each other despite distinct chemical compositions, forming dark, fine-grained rocks, with

1380-554: The eruptive sequence at Cinder Cone took place over the course of several months. An unusual characteristic of the Fantastic Lava Beds is the presence of anomalous quartz crystal xenocrysts (foreign bodies in igneous rock ). Geologists think that they were picked up from wall rocks by the lava as it moved toward the surface. After traveling through Northern California in the spring of 1851, two gold prospectors reported seeing an erupting volcano that "threw up fire to

1426-431: The first of which was mostly destroyed by lava flows from its base. Cinder cone volcanoes are typically monogenetic , meaning that they only undergo one eruptive period before ceasing activity forever. These eruptions often consist of the ejection of tephra , though they may also generate lava flows, which often originate from vents near the base rather than the summit of the volcanic edifice. The summit of Cinder Cone has

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1472-521: The flanks of Mauna Kea , a shield volcano located on the island of Hawaii . Such cinder cones likely represent the final stages of activity of a mafic volcano. However, most volcanic cones formed in Hawaiian-type eruptions are spatter cones rather than cinder cones, due to the fluid nature of the lava. The most famous cinder cone, Paricutin , grew out of a corn field in Mexico in 1943 from

1518-554: The lake's floor, run along the edges of the Fantastic Lava Beds and mark the margins of this former lake. Cinder Cone is a 700 ft (210 m)-high volcanic cone of loose scoria . The youngest mafic volcano in the Lassen volcanic center, it is surrounded by unvegetated block lava and has concentric craters at its summit, which have diameters of 1,050 ft (320 m) and 590 ft (180 m). Cinder Cone comprises five basaltic andesite and andesite lava flows, and it also has two cinder cone volcanoes, with two scoria cones,

1564-446: The molten lava is denser than the bubble-rich cinders. Thus, it often burrows out along the bottom of the cinder cone, lifting the less dense cinders like corks on water, and advances outward, creating a lava flow around the cone's base. When the eruption ends, a symmetrical cone of cinders sits at the center of a surrounding pad of lava. If the crater is fully breached, the remaining walls form an amphitheater or horseshoe shape around

1610-500: The rings of one particular tree, which showed two periods of slow growth, he thought that the two explosive eruptions occurred in 1567 and 1666. He also concluded that the five lava flows were extruded in 1567, 1666, 1720, 1785, and 1851. After Finch published his work in 1937, few additional studies were done on volcanic hazards in the Lassen area. However, that changed after the 1980 eruption of Mount St. Helens in Washington . As

1656-559: The sky from a volcanic eruption from a location west of the Lassen area. Receiving widespread attention, the article was widely reprinted, despite the fact that the account lacked specific dates or locations for their claims. Poking fun at Wozencraft's claims, the Shasta Republican wrote several times throughout April 1859 that "the Dr.'s imagination is far more active than any volcano in our County or State." Harkness' 1875 report cites

1702-699: The solar system. On Mars, they have been reported on the flanks of Pavonis Mons in Tharsis , in the region of Hydraotes Chaos on the bottom of the Coprates Chasma , or in the volcanic field Ulysses Colles . It is also suggested that domical structures in Marius Hills (on the Moon) might represent lunar cinder cones. The size and shape of cinder cones depend on environmental properties as different gravity and/or atmospheric pressure might change

1748-469: The time of eruption can cause a greater accumulation of cinder on the downwind side of the vent. Some cinder cones are monogenetic , forming from a single short eruptive episode that produces a very small volume of lava. The eruption typically last just weeks or months, but can occasionally last fifteen years or longer. Parícutin in Mexico, Diamond Head , Koko Head , Punchbowl Crater , Mt Le Brun from

1794-431: The upper part of the ash layer, and the two Fantastic Lava Beds flows. Radiocarbon dating places these occurrences between 1630 and 1670 CE. At the Old Bench and Painted Dunes lava flows, the volcanic ash is brightly oxidized because it interacted with the lava flows when they were still hot. It shares its compositional group with the Fantastic Lava Beds flows, which represent the last flows erupted at Cinder Cone. Ultimately,

1840-443: The vent. Basaltic cinder cones are the most characteristic type of volcano associated with intraplate volcanism . They are particularly common in association with alkaline magmatism , in which the erupted lava is enriched in sodium and potassium oxides . Cinder cones are also commonly found on the flanks of shield volcanoes , stratovolcanoes , and calderas . For example, geologists have identified nearly 100 cinder cones on

1886-462: The volcanic deposits at Cinder Cone were complex and are by no means completely understood. However, the new studies done by USGS scientists refute the purported accounts of an eruption in the early 1850s and confirm Diller's (1891, 1893) interpretation that Cinder Cone erupted in the latter half of the 17th century. They also suggest that the 1666 tree-ring date proposed by Finch (1937) for his "second" explosive eruption at Cinder Cone might actually date

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1932-404: The youngest lava flow was extruded in 1851, accepting Harkness' (1875) historical "evidence" and ignoring Diller's interviews and conclusions; and (3) that there had been at least two distinct explosive eruptions of the cone. Using these assumptions and tree-ring measurements, Finch proposed a complex and detailed eruptive chronology for Cinder Cone that spanned nearly 300 years. From measurements of

1978-707: Was "certainly" sometime before 1840. On May 6, 1907, both Cinder Cone and Lassen Peak were designated national monuments, administered by the National Forest Service . Cinder Cone's name was officially recognized by the United States Board on Geographic Names in 1927. In the mid-1930s, USGS volcanologist R. H. Finch attempted to improve on Diller's work. On the basis of other studies done at Cinder Cone, Finch thought (1) that there had been at least five separate lava-flow events, as suggested by crude, experimental magnetic measurements; (2) that

2024-434: Was extremely unlikely that an eruption could have occurred there in the winter of 1850. He also noted that trees rooted in volcanic ash erupted from the cone were about 200 years old and that the oldest trees on related lava flows were about 150 years old. Diller believed he recognized two eruptive sequences, which each produced lava flows. However, he thought that only the older eruption was explosive, creating Cinder Cone and

2070-687: Was formed during two eruptions that occurred in the 1650s. Cinder Cone lies in Lassen and Shasta counties, in Northern California , within the United States. Located 1.5 mi (2.4 km) southwest of Butte Lake and 2.2 mi (3.5 km) southeast of Prospect Peak (which dwarfs Cinder Cone), it is also sometimes referred to as Black Butte or Cinder Butte. The volcano lies in the northeastern corner of Lassen Volcanic National Park . Nearby Snag Lake formed when lava known as

2116-514: Was snuffed out when several basalt lava flows erupted from its base. These flows, called the Fantastic Lava Beds , spread northeast and southwest, and dammed creeks, first creating Snag Lake on the south and then Butte Lake to the north. Butte Lake is fed by water from Snag Lake seeping through the lava beds. Nobles Emigrant Trail goes around Snag Lake and follows the edge of the lava beds. Its age has been controversial since

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